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51.
This study aims to develop highly durable, mineral carbonation-based, resource-recycling, secondary cement products based on supercritical carbon dioxide (CO2) curing as part of carbon capture utilization technology that permanently fixes captured CO2. To investigate the basic characteristics of secondary cement products containing concrete sludge waste (CSW) as the main materials after supercritical CO2 curing, the compressive strengths of the paste and mortar (fabricated by using CSW as the main binder), ordinary Portland cement, blast furnace slag powder, and fly ash as admixtures were evaluated to derive the optimal mixture for secondary products. The carbonation curing method that can promote the surface densification (intensive CaCO3 formation) of the hardened body within a short period of time using supercritical CO2 curing was defined as “Lean Carbonation”. The optimal curing conditions were derived by evaluating the compressive strength and durability improvement effects of applying Lean Carbonation to secondary product specimens. As a result of the experiment, for specimens subjected to Lean Carbonation, compressive strength increased by up to 12%, and the carbonation penetration resistance also increased by more than 50%. The optimal conditions for Lean Carbonation used to improve compressive strength and durability were found to be 35 °C, 80 bar, and 1 min.  相似文献   
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53.
Vasospasm, initial neurological damage, rebleeding, and periprocedural complications are associated prognostic factors for clinical outcomes after aneurysmal subarachnoid hemorrhage (SAH). In this study, factors related to delayed ischemic neurological deficit (DIND) are evaluated using data from our institute for the last 18 years. Data from 2001 to 2018 of patients with aneurysmal SAH who underwent surgical clipping (SC) or endovascular coiling (EC) within 7 days of onset were retrospectively analyzed. Cases of mortality within 5 days after treatment were excluded. Multivariate analysis was used to identify the risk factors for DIND. In total, 840 cases of SAH were assessed; among these cases, 384 (45.7%) and 456 (54.3%) were treated with SC and EC, respectively. The frequency of DIND in the EC group was significantly less than that in the SC group (11.8% vs. 17.7%; p = 0.016). In the results of multivariate analysis, internal carotid artery (ICA) aneurysm and hemorrhagic complications were the risk factors for DIND. Cilostazol administration and EC were significant factors for vasospasm prevention after aneurysmal SAH (odds ratio of ICA aneurysm: 1.59, hemorrhagic complications: 1.76, SC: 1.51, and cilostazol administration: 0.51, respectively). Cilostazol administration was also a significant factor in patients who were treated with EC. ICA aneurysm, treatment strategy, hemorrhagic complications, and cilostazol administration were associated with DIND. Oral administration of cilostazol and avoiding hemorrhagic complications were effective in DIND prevention. If both treatments are available for ruptured aneurysms, clinicians should choose EC on the basis of its ability to prevent DIND.  相似文献   
54.
Objective The aim of the study was to develop a checklist for mental health clinicians to predict and manage suicidality. Methods A literature review of the risk and protective factors for suicide was conducted to develop a checklist for evaluating suicidality. Results The fixed risk factors included sex (male), age (older individuals), history of childhood adversity, and a family history of suicide. Changeable risk factors included marital status (single), economic status (poverty), physical illness, history of psychiatric hospitalization, and history of suicide attempts. Recent discharge from a mental hospital and a recent history of suicide attempts were also included. Manageable risk factors included depression (history and current), alcohol problems (frequent drinking and alcohol abuse), hopelessness, agitation, impulsivity, impaired reality testing, and command hallucinations. Protective factors included responsibility to family, social support, moral objections to suicide, religiosity, motivation to get treatment, ability to cope with stress, and a healthy lifestyle. A final score was assigned based on the sum of the risk and protective factor scores. Conclusion We believe that the development of this checklist will help mental health clinicians to better assess those at risk for suicidal behavior. Further studies are necessary to validate the checklist.  相似文献   
55.
We investigated whether dining with companions is correlated with the alleviation of depression and differs by sex among Korean adults. We used 4-year data from the 2014, 2016, 2018, and 2020 Korea National Health and Nutrition Examination Survey. We surveyed 11,055 participants (4699 men, 6356 women) using the Patient Health Questionnaire-9 to measure their depression scores. We evaluated participants’ meal companionship status by asking whether they had usually dined with companions for breakfast, lunch, or dinner during the past year. Statistical analysis was performed using chi-square tests and multivariate/multinomial logistic regression. We found depression to be less prevalent among participants who dined with companions at least once a day (adjusted OR: 0.26, 95% CI: 0.15–0.45, men; adjusted OR: 0.50, 95% CI: 0.34–0.74, women). In the moderate depression subgroup, participants who dined with companions at least once a day showed lower OR (adjusted OR: 0.28, 95% CI: 0.16–0.50, men; adjusted OR: 0.50, 95% CI: 0.32–0.76, women). Among participants who dined together, men’s severe depression dramatically decreased (adjusted OR: 0.05, 95% CI: 0.01–0.31). Thus, we found an association between dining with companions and the prevalence of depression among Korean adults. Dining with companions compared with dining alone signified a lower depression rate, especially among men. This study can provide an initiative to further analyze psychological and physiological effects of dining together and be applied to practical fields as education and societal campaigns.  相似文献   
56.
The coronavirus disease 2019 (COVID-19) resulted in a marked decrease in the number of patient visits for acute myocardial infarction and delayed patient response and intervention in several countries. This study evaluated the effect of the COVID-19 pandemic on the number of patients, patient response time (pain-to-door), and intervention time (door-to-balloon) for patients with ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI).Patients with STEMI or NSTEMI visiting a hospital in South Korea who underwent primary coronary intervention during the COVID-19 pandemic (January 29, 2020, to December 31, 2020) were compared with those in the equivalent period from 2018 to 2019. Patient response and intervention times were compared for the COVID-19 pandemic window (2020) and the equivalent period from 2018 to 2019.We observed no decrease in the number of patients with STEMI (P = .88) and NSTEMI (P = 1.00) during the COVID-19 pandemic compared to that in the previous years. Patient response times (STEMI: P = .39; NSTEMI: P = .59) during the overall COVID-19 pandemic period did not differ significantly. However, we identified a significant decrease in door-to-balloon time among patients with STEMI (14%; P < .01) during the early COVID-19 pandemic.We found that the number of patients with STEMI and NSTEMI was consistent during the COVID-19 pandemic and that no time delays in patient response and intervention occurred. However, the door-to-balloon time among patients with STEMI significantly reduced during the early COVID-19 pandemic, which could be attributed to decreased emergency care utilization during the early pandemic.  相似文献   
57.
<正>1Department of Emergency Medicine, Chungnam National University Hospital, Daejeon 35015, South Korea2Department of Emergency Medicine, College of Medicine, Chungnam National University, Daejeon 35015, South Korea3Forensic Toxicology Division, National Forensic Service, Daejeon 34054, South Korea4Department of Emergency Medicine, Chungbuk National University Hospital, Cheongju 28644, South Korea Corresponding Author:Wonjoon Jeong, Email:gardenjun@hanmail.net  相似文献   
58.
Background  The technical difficulty of lymph node dissection in laparoscopy-assisted distal gastrectomy (LADG) remains a barrier for extending the indication for this modality and limits its widespread clinical practice. The aim of this study was to evaluate our institutional guidelines for LADG, limiting the indications for this modality to only clinical stage T1N0 or T1N1 gastric cancer. Methods  From January 2002 to October 2006, a total of 294 cases of LADG and 664 cases of open distal gastrectomy (ODG) for clinical T1N0 or T1N1 gastric cancer were performed at the National Cancer Center, Korea. The two groups’ clinicopathologic characteristics, surgical outcome, morbidity, and survival were compared. Results  The mean operating time for the LADG group was significantly longer than that for the ODG group (265.8 ± 56.3 vs. 171.4 ± 43.1 minutes, P < .001). The mean number of retrieved lymph nodes in the LADG group was higher than that of the ODG group (39.5 ± 14.7 vs. 37.2 ± 12.9, P = .017). The postoperative hospital stay was shorter in the LADG group (8.0 ± 3.3 vs. 10.5 ± 4.1 days, P < .001). The complications rate was lower for the LADG group than that for the ODG group (6.8% vs. 11.3%, P = .032). The overall survival rate was not significantly different between the two groups (P = .880). Conclusions  Before considering expanding the indications for LADG, developing a carefully thought-out guideline and conducting an audit are mandatory.  相似文献   
59.
Background Information on surgical complications of laparoscopy-assisted distal gastrectomy (LADG) and their risk factors is limited in the literature despite increasing popularity of this procedure. This study was performed to identify the surgical complications and their associated risk factors of LADG in early gastric cancer. Methods LADG was performed in 347 gastric cancer patients from January 2002 to December 2006 at the Korean National Cancer Center by four surgeons with ample experience of open gastric surgery before LADG. LADG indications for cases of gastric cancer at our institution are preoperatively diagnosed cT1N0 or cT1N1, except in cases with an absolute indication for endoscopic resection. Lymph node dissection of more than D1 + β was performed in all patients. Intraoperative and postoperative complications were reviewed and their risk factors were retrospectively analyzed by prospective database information. Results Forty complications occurred in 34 patients (9.8%), but there was no mortality. Intraoperative complications occurred in nine patients (2.6%), and open conversion was performed in eight (2.3%) of these patients. Early and late postoperative complications occurred in 21 (6.1%) and 10 (2.9%) patients, respectively. The most serious complication was vascular injury resulting in bleeding or organ ischemia, which occurred in seven patients. Degree of lymph node dissection and surgical inexperience were found to be risk factors of surgical complication (P = .023, odds ratio 2.832, 95% confidence interval 1.155–6.946 vs. P = .028, odds ratio 2.975, 95% confidence interval 1.127–7.854). Conclusions Lymph node dissection during LADG should be performed cautiously to prevent surgical complications like vascular injuries, especially during the surgeon’s early learning period.  相似文献   
60.
Factors affecting the registration error (RE) and motion of focal hepatic lesions (FHLs) in image fusion of real-time ultrasonography (US) with computed tomography (CT) images were prospectively assessed by focusing on respiratory movement and FHL location. Real-time US and pre-acquired CT images at end-inspiration were fused with FHLs for 103 patients. Three-dimensional US data containing FHLs were obtained during end-inspiratory/expiratory phases. Multivariate analysis revealed that diaphragm motion (p < 0.001), chronic liver disease (p = 0.02) and the absolute difference in distance between the FHL and the central portal vein (CPV) during respiration (p = 0.03) were the independent factors that revealed the maximum effect on RE. In contrast, diaphragm motion (p < 0.001) and distance between the FHL and CPV at inspiration (p = 0.036) revealed the maximum effect on FHL motion. In conclusion, RE and FHL motion are affected by the degree of respiratory movement and the location of the FHL. Therefore, image fusion with CT images should be used with caution if the degree of respiratory motion is significant or if the FHL is located at the periphery of the liver.  相似文献   
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